Latent Semantic Analysis (“LSA”) is a modern algorithm that is used in many applications for discovering latent relationships in data. In one such application, LSA is used in the analysis and searching of text documents. Given a set of two or more documents, LSA provides a way to mathematically determine which documents are related to each other, which terms in the documents are related to each other, and how the documents and terms are related to a query. Additionally, LSA may also be used to determine relationships between the documents and a term even if the term does not appear in the document.
LSA utilizes Singular Value Decomposition (“SVD”) to determine relationships in the input data. Given an input matrix representative of the input data, SVD is used to decompose the input matrix into three decomposed matrices. LSA then creates compressed matrices by truncating vectors in the three decomposed matrices into smaller dimensions. Finally, LSA analyzes data in the compressed matrices to determine latent relationships in the input data.